common seal - Subspecies, Behaviour and reproduction

A true seal native to N Pacific and N Atlantic Oceans (Phoca vitulina); usually grey with dark blotches; may dive deeper than 90 m/300 ft; eats fish, squid, and crabs; also known as harbour seal or hair seal.

iCommon Seal
Conservation status
Least concern (LR/lc)
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Suborder: Pinnipedia Family: Phocidae Genus: Phoca Species: P. vitulina
Binomial name
Phoca vitulina Linnaeus, 1758
Range of Phoca vitulina

The Common Seal (UK, Ireland), Harbor Seal (U.S.) or Harbour Seal (Canada), Phoca vitulina is a true seal of the Northern Hemisphere. While it is legal to kill seals which are perceived to threaten fisheries in the United Kingdom, Norway and Canada, commercial hunting is illegal; the seals are also taken in subsistence hunting and accidentally as bycatch in fishing nets. In the United States stricter protection applies, and it is illegal to kill any seals or any marine mammals, as they fall under the Marine Mammal Protection Act. A relatively large (for a seal) ear canal may be visible posterior to the eye.

Female common seals have a life span of 30-35 years while male lifespans are usually 20-25. Scientists have suggested that this is due to stresses male seals are subjected to during breeding seasons.

Subspecies

There are four or five subspecies:

Western Atlantic Harbor Seal Phoca vitulina concolor (DeKay, 1842). Ungava seal Phoca vitulina mellonae (Doutt, 1942). concolor by many authors) Pacific Harbor Seal Phoca vitulina richardii (Gray, 1864). Insular Seal Phoca vitulina stejnegeri (Allen, 1902). Eastern Atlantic Common Seal Phoca vitulina vitulina (Linnaeus, 1758). They are one of the most common seal in the world. some seals may also enter estuaries in pursuit of their fish prey. The seals frequently choose to congregate in harbours, lending the animals their other common name.

Behaviour and reproduction

While not forming groups as large as some other seals, they are gregarious animals. When not actively feeding, the seals will haul themselves out of the water and onto a preferred resting site. The seals tend to hug the coast, not venturing more than 20 kilometres offshore.

Common Seals must spend a great deal of time on shore when moulting (shedding of their fur), which the seals undergo shortly after breeding. This pinniped is sometimes reluctant to haul out in the presence of humans, so that shoreline development and access must be carefully studied in known locations of seal haul out (Deghi, 1986). Pacific harbor seals or Californian harbor seals are found along the entire Pacific coast shoreline of the state. Some of the best locations for viewing Harbor Seals up close are at Cannery Row in Monterey, Moss Landing on Monterey Bay or at Bolinas Lagoon in Marin County. As top level feeders in the kelp forest, Harbor Seals enhance species diversity and productivity.

Considerable scientific inquiry has been carried out by The Marine Mammal Center and other research organizations beginning in the 1980s regarding the incidence and transmission of diseases in Harbor seals in the wild, including analysis of phocine herpesvirus (Goldstein, 2004). ARKive - images and movies of the common seal. SealWatch.org - photos of harbor seal haulouts from Alaska to the UK. Harbor seals. CRC Handbook of Marine Mammal Medicine, edited by Leslie A Dierauf, Frances M D Gulland,, CRC Press (2001) ISBN 0-8493-0839-9 Joan Hewitt, A Harbor Seal Pup Grows Up, Carolrhoda Books (2002) ISBN 1-57505-166-4 T.C. Marine Mammals of Eastern North Pacific and Arctic Waters, Pacific Search Press, Seattle WA (1978) Goldstein, T., Mazet, J.A.K., Gullan, F.M.D., Rowles, T., Harvey, J.T., Allen, S.G., King, D.P., Aldridge, B.M., Stott, J.L., "The transmission of phocine herpesvirus-1 in rehabilitating and free-ranging Pacific harbor seals (Phoca vitulina) in California", Veterinary Microbiology 103:131-141 (2004)